MWISP G110.900-02.509 , the SIMBAD biblio

We have conducted a large-field simultaneous survey of ¹²CO, ¹³CO, and C¹⁸O J = 1 - 0 emission toward the Cassiopeia A (Cas A) supernova remnant (SNR), which covers a sky area of 3.°5 x 3.°1. The Cas giant molecular cloud (GMC) mainly consists of three individual clouds with masses on the order of 10⁴-10⁵ M_☉. The total mass derived from the ¹³CO emission of the GMC is 2.1 x 10⁵ M_☉ and is 9.5 x 10⁵ M_☉ from the ¹²CO emission. Two regions with broadened (6-7 km s^–1) or asymmetric ¹²CO line profiles are found in the vicinity (within a 10' x 10' region) of the Cas A SNR, indicating possible interactions between the SNR and the GMC. Using the GAUSSCLUMPS algorithm, 547 ¹³CO clumps are identified in the GMC, 54% of which are supercritical (i.e., α_vir < 2). The mass spectrum of the molecular clumps follows a power-law distribution with an exponent of -2.20. The pixel-by-pixel column density of the GMC can be fitted with a log-normal probability distribution function (N-PDF). The median column density of molecular hydrogen in the GMC is 1.6 x 10²¹ cm^–2 and half the mass of the GMC is contained in regions with H₂ column density lower than 3 x 10²¹ cm^–2, which is well below the threshold of star formation. The distribution of the YSO candidates in the region shows no agglomeration.